This invention relates generally to the field of processing digital data used in the field of consumer electronics. More particularly, this invention relates to the demultiplexing and storage of digital data for use in audio visual equipment.
Digital information for use by audio-visual equipment is often transmitted in packets. Often the packets are organized according to one of the many standards that have been established by various technology standards committees. For example, MEPG-2 is a standard that is used in the telecommunications industry. The way in which the packets of information are handled is important, because it impacts the speed at which data can be transmitted and the resulting operations which can be performed on the audio visual data. For example, the ability to transmit a frame from a movie at a fast rate permits additional operations to be performed on the frame without impacting the speed at which the movie is shown.
One type of device used in the telecommunications or consumer electronics industry is the Digital Video Disc (DVD) player. DVD players in the past have relied on a buffer, known as a track buffer, to store data as the data is read from the DVD disk. The information is then stored in the buffer until each packet of DVD data can be parsed into its subcomponents. Once the data is parsed into its subcomponents, such as an audio portion, a video portion, a subpicture portion, and a navigation portion, it can be stored for later decoding and processing.
A drawback to prior DVD players has been that the track buffer was required prior to the data being parsed. This has been due to the fact that prior hardware designs have focused on the decoder speed as the determining factor in the hardware design. As a result, when data is read from a DVD disc, it must be stored until the decoder(s) are finished processing the preceding data.
A further drawback to such designs is that the additional component of a track buffer is required prior to the demultiplexing of data. This serves as an additional component which the data must travel through and which can possibly corrupt the data signal being read from the DVD disc. Furthermore, it adds to the cost and weight of the DVD player.
Hence, there is a need for a design that does not require the use of a track buffer for storage of data prior to the parsing of the data. Furthermore, there is a need for a simpler design that reduces the number of components for processing of DVD data.
The present invention provides a system to overcome these disadvantages and satisfy the needs highlighted by other designs. The system of the present invention provides an input to receive data from a drive of a DVD player; a demultiplexer to parse the data, without the need for a track buffer between the DVD disc and the demultiplexer. Furthermore, the invention is capable of receiving a data stream from a DVD disc, wherein the datastream is composed of audio data, video data, etc. all packetized into a standardized packet; demultiplexing the data stream to separate each of the data portions; while once again not requiring the use of a track buffer prior to the act of demultiplexing the data stream.
Further embodiments of the invention can be accomplished by using track buffer(s) coupled to the output of the demultiplexer and decoder(s) to decode each respective data portion. Separate track buffers can be used for each respective portion of data, e.g., an audio track buffer, a video track buffer, a subpicture track buffer, and a navigation track buffer. The track buffer(s) can be stored in random access memory, such as Synchronized Dynamic Random Access Memory (SDRAM).
In accordance with another embodiment of the invention, the decoding of data is synchronized to the speed of the DVD drive so as to eliminate the need for an additional data storage device.